Lithium ion battery

Patent metadata

Field	Value
Publication number	US-2025286134-A1
Application number	US-202318862168-A
Country	US
Kind code	A1
Filing date	Jun 7, 2023
Priority date	Jun 16, 2022
Publication date	Sep 11, 2025
Grant date	—

Abstract

To address the issue that the existing lithium ion battery with positive electrode containing manganese impacts battery performance, the application provides a lithium ion battery, which includes a positive electrode, a negative electrode, a non-aqueous electrolyte and a separator, and the separator is positioned between the positive and negative electrodes, the positive electrode includes a positive electrode material layer, the positive electrode material layer includes a lithium manganese-based positive electrode active material, the non-aqueous electrolyte includes a non-aqueous organic solvent, a lithium salt and an additive, and the additive includes a compound represented by structural formula 1:the lithium ion battery meets the following requirements:0.1≤q*m/p≤20;and⁢20≤q≤6⁢0,0.0⁢1≤m≤2,1.5≤p≤5;The lithium ion battery can enhances safety by reducing ion exchange between Mn2+ and lithium in the negative electrode, prevent manganese from damaging the negative electrode, and increasing electrode stability, ensuring high energy density and cycle performance.

First claim

1 . A lithium ion battery, comprising a positive electrode, a negative electrode, a non-aqueous electrolyte and a separator, wherein the separator is positioned between the positive electrode and the negative electrode, the positive electrode comprises a positive electrode material layer, the positive electrode material layer comprises a lithium manganese-based positive electrode active material, the non-aqueous electrolyte comprises a non-aqueous organic solvent, a lithium salt and an additive, and the additive comprises a compound represented by structural formula 1:

wherein n is 0 or 1, X is selected from

 R 1 and R 2 are each independently selected from H, a C1-C5 hydrocarbon group,

and at least one of X, R 1 , and R 2 comprises a sulfur atom;
the lithium ion battery meets the following requirements:

0
.1

≤

q
*
m
/
p

≤
20

;

and
⁢

20

≤
q
≤

6
⁢
0

,

0
.
0

⁢
1

≤
m
≤
2

,

1.5
≤
p
≤
5

;

where q is a porosity of the separator, and the unit is %;
m is a percentage mass content of the compound represented by structural formula 1 in the non-aqueous electrolyte, and the unit is %; and
P is a capacitance per unit area of the positive electrode material layer, and the unit is mAh/cm 2 .

2 . The lithium ion battery of claim 1 , wherein the lithium ion battery meets the following requirements:
1 ≤q*m/p≤ 10.

3 . The lithium ion battery of claim 1 , wherein the porosity (q) of the separator is 30%-50%.

4 . The lithium ion battery of claim 1 , wherein the percentage mass content (m) of the compound represented by structural formula 1 in the non-aqueous electrolyte is 0.1%-1%.

5 . The lithium ion battery of claim 1 , wherein the capacitance per unit area (p) of the positive electrode material layer is 2-4 mAh/cm 2 .

6 . The lithium ion battery of claim 1 , wherein the compound represented by structural formula 1 is selected from one or more of the following compounds:

7 . The lithium ion battery of claim 1 , wherein the lithium manganese-based positive electrode active material comprises one or more compounds represented by formula (A), formula (B) and formula (C):
Li 1+x Mn a Ni b M 1−a−b O 2−y A y   Formula (A)
Li 1+z Mn c N 2−c O 4−d B d   Formula (B)
LiMn q Fe 1−q PO 4   Formula (C)
in formula (A), −0.1≤x≤0.2, 0<a<1, 0≤b<1, 0<a+b<1, 0≤y<0.2, M is one or more of Co, Fe, Cr, Ti, Zn, V, Al, Zr and Ce, and A comprises one or more of S, N, F, Cl, Br and I; in formula (B), −0.1≤z≤0.2, 0<c≤2, 0≤d<1, N comprises one or more of Ni, Fe, Cr, Ti, Zn, V, Al, Mg, Zr and Ce, and B comprises one or more of S, N, F, Cl, Br and P; and in formula (C), 0<q<1.

8 . The lithium ion battery of claim 1 , wherein at least one surface of the separator is coated with a surface coating, and the surface coating comprises one or more of an inorganic particle and an organic gel.

9 . The lithium ion battery of claim 1 , wherein a content of manganese in the separator per unit area is 50 ppm/m 2 −2000 ppm/m 2 .

10 . The lithium ion battery of claim 1 , wherein the additive further comprises at least one of cyclic carbonate compound, unsaturated phosphate compound, borate compound and nitrile compound.

11 . The lithium ion battery of claim 10 , wherein the content of the additive is 0.01%-30/o based on the total mass of the non-aqueous electrolyte being 100%.

12 . The lithium ion battery of claim 10 , wherein the cyclic carbonate compound is selected from at least one of vinylene carbonate, vinylethylene carbonate, fluoroethylene carbonate or a compound represented by structural formula 2;

in structural formula 2, R 21 , R 22 , R 23 , R 24 , R 25 and R 26 are each independently selected from one of a hydrogen atom, a halogen atom and a C1-C5 group.

13 . The lithium ion battery of claim 10 , wherein the unsaturated phosphate compound is selected from at least one of the compounds represented b structural formula 3:

in structural formula 3, R 31 , R 32 and R 33 are each independently selected from a C1-C5 saturated hydrocarbon group, an unsaturated hydrocarbon group, a halogenated hydrocarbon group and —Si(C m H 2m+1 ) 3 , m is a natural number of 1-3, and at least one of R 31 , R 32 and R 33 is an unsaturated hydrocarbon group.

14 . The lithium ion battery of claim 10 , wherein the borate compound is selected from at least one of tris (trimethylsilane) borate and tris (triethyl silicane) borate.

15 . The lithium ion battery of claim 10 , wherein the nitrile compound is selected from one or more of butanedinitrile, glutaronitrile, ethylene glycol bis (propionitrile) ether, hexanetricarbonitrile, adiponitrile, pimelic dinitrile, hexamethylene dicyanide, azelaic dinitrile and sebaconitrile.

Assignees

• Shenzhen Capchem Technology Co Ltd

Inventors

• Qian Yunxian
• Hu Shiguang
• Li Hongmei
• Xiang Xiaoxia

Classifications

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/4235

  Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence) · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title